One of the reasons why many people don't like TT bits and the like is because when you think about the leverage ratio; a simple snaffle bit is a 1:1 ratio (you exert 1 pound of pressure on the reins and the horse feels 1 pound of pressure in his mouth). The ratio all depends on the proportions of the bit but I think a standard TT is a 1:3 ratio (each pound you exert, the horse feels 3).
Tom Thumb Bit
And here is another site that explains the confusion caused by direct reining, etc.
Trouble with Tom Thumb
And as for the bar across the bottom of the bit, it is called a slobber bar and I believe it is just used to stabilize the swivel motion on longer shanked bits. Not positive though.
Copied from another forum and it sounds right...
| Bit hobble, shank hobble, slobber strap, slobber bar, slobber chain...many names. Sometimes it's a thin bar, or a thick one. Some have chain, some are just a rope or braided rope/rawhide. You could use a curb strap if it goes small enough. It also has the effect of fixing loose shanks. It won't make them 100% stiff but it takes a lot of the play out of them so that they act more like a stiff shank then a loose one. |
If the shanks are long it won't stop it from flipping over. What it is normally for is to stop a rope(or other things but mainly a rope) from getting hung up int he shanks and getting the mouth jerked on when the rope is pulled tight.